This is an original OEM Sparco Plastic Binding Spine, designed for use with Fellowes, GBC, and other compatible binding machines. It features a durable construction that will not scratch, chip, peel, or discolor, ensuring a professional finish for your documents. The spine holds up to 55 sheets and has a diameter of 3/8 inch, making it suitable for various binding needs. Each box contains 100 spines, providing ample supply for your office or project requirements.